My Home Ideas

Special Offers

Be the first to know about This Old House contests, sweepstakes, and events and receive special offers and promotions from your favorite home improvement brands. We'll even send you regular reminders to enter our sweepstakes.

Contribute to This Story Below

More in Health & Safety

Pile Supports

Site conditions influence whether wood or masonry piles with concrete footings will provide enough structural support or whether helical steel piles, which are installed in sections, are called for.

Helical piles:The optimal solution in unstable soils, such as sand or peat, these are made from short—about 5 feet long—steel segments bolted end-to-end on-site. They get rotated into the ground by machine (as shown) and can be installed where traditional wood piles cannot fit under an existing house. Screw-like plates (inset) cause less soil disturbance than traditional excavation. The piles can be tied directly into the building structure or into conventional concrete footings.